nikhilvsh wrote:
Hello,
Please review this solution -
1. When any 2 numbers are picked from a set of distinct numbers, say 'a' first and then 'b', the probability of a>b will be 0.5 and probability for a<b is 0.5. So, if n numbers are picked one after another, then the probability in all cases would be. (0.5)^n.
So all we need is the value of 'n'.
Hence, B iscorrect.
Check here: https://gmatclub.com/forum/m27-184482-40.html#p2964973
When you select 2, you can arrange them in 2 ways:
smaller, greater
greater smaller
When you select 3, you can arrange them in 3! ways only one of which is the ascending order.
small, mid, large (ascending order)
mid, small, large
small, large, mid
mid, large, small
large, small, mid
large, mid, small
Similarly, when you select 5, you can arrange them in 5! ways only one of which is in ascending order.
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Statistics : Posted by KarishmaB • on 16 Sep 2014, 00:27 • Replies 45 • Views 71787
